Posted on Instagram with the following text:
“Thanks Scott for the latest update!
Right now the testing of the equipment is in progress.”
The devices shown in the first picture are:
SPCM50A/M – Single Photon Counter Module, 350 – 900 nm, 50 µm, M4 Tap (link)
The Thorlabs SPCMxxA uses a silicon avalanche photo diode (Si APD), operated in reverse di-rection and biased slightly beyond the avalanche threshold (Geiger mode). An incident photongenerates charge carriers, which initiate a current pulse. In order to enable the count of next incident photon, each current pulse must be “quenched” bylowering the bias voltage below the avalanche threshold for a short time. After quenching thebias increases again, this way enabling the APD for detection of the next photon. The ThorlabsSPCMxxA use an APD with integrated quenching circuit, providing a high counting accuracy.Photon initiated current pulses are counted. The counter is gated for a certain time (“bin”).Measurement can be repeated in order to count the number of incident photons in subsequentbins.